They say you should practice what you preach, and when it comes to family traditions, I have surely tried.

I began to write my first book on family traditions while I was still pregnant with my son, and while I interviewed experts and families all over the country, I kept getting inspired to be creative in my own rituals and celebrations. Not everything worked, but if there is one single tradition of my own invention that really has come to be treasured, it is our “birthday sheets.” (Like many of my personal traditions, it is included in the new edition of The Book of New Family Traditions. For those who are not aware, all of my books go way beyond my own ideas and practices and are based on interviews with hundreds of other families.)

I remember when my son was about to turn 3. I was still working on The Heart of a Family and reading a lot of books about traditions in many times and places. I was fascinated by tribal rites of passage, and by the notion that when a person marks a milestone in his or her life, they should have a concrete feeling of actually crossing over a threshold. I felt that my son was changing profoundly from a baby to a child, as he entered nursery school, got potty trained, and experienced many other “firsts.” I thought long and hard about how I could somewhow create a physical barrier that he would cross through to symbolize and celebrate this change. Should I buy wood and erect something? Could I fashion a structure out of twigs, or tie two saplings together to make an arch? Everything seemed too complicated and beyond my skills.

Somehow, a lightbulb turned on: I could create a threshold simply by taking a white bed sheet and painting it with symbols of “big boyness,” like underpants. I would tape the sheet over the entrance to the family room, and cut a slit up from the ground as high as my son’s head, and he would go “through” the sheet to find his presents on the other side. He would feel an element of venturing into the unknown, of taking a leap of faith, I hoped. That first year, I explained the concept while I held him in my arms, after a birthday dainner with cake and all the trimmings. He got very excited when I set him down, and he raced through the opening . I assumed he would immediately tear into his gifts, but the experience of racing back and forth through the sheet was just way too much fun to stop. Suddenly, these familiar rooms became mysterious: it was like playing hide and seek with an entire room!

My assumption was that these Milestone Sheets would be few and special. I already planned to make one for his 5th birthday, and expected the next to happen at age 10. But before his 7th birthday, Max began pleading for a sheet, explaining that he earned it. “I can do so many things I couldn’t do at 5!” he insisted. So that sheet was all about his important new skills, whereas the 5th birthday sheet led to a Pirate’s Treasure.

For this 10th birthday, I had a lot of fun painting characters he loved, like the Pokemon called Pikachu, and also Bart Simpson, who was (and always will be) 10 years old.

For the milestone sheet at 13, I again painted a lot of my son’s favorite things, including a wizardy looking woman of unknown species from World of Warcraft, the video game, as well as the mean cat Bucky from the Get Fuzzy comics. I also added 13 lizards, one for each year (and for luck), because my son owned and loved lizards.

Interestingly, the sheets for age 10 and 13 never got “cut” up from the bottom, because my son felt they were too precious. He decided to go around them into the family room instead.

I thought that his 13th birthday would be the end of the sheets, but before he turned 18, Max informed me that he very much wanted and expected to return to the tradition for this major coming-of-age. Unfortunately, this happened around the time of Hurricane Sandy and we lost power for a week, just as I was struggling for an inspiration of how to illustrate this milestone on cloth. Eventually, I grasped at the idea of the unknown, that Max was soon to leave us, after this senior year of high school, and he truly was entering the mystery of his adult identity. I decided to illustrate this point by cutting question marks out of a bunch of fabrics that represented things that Max loved, like reptiles and Japanese Anime. I even found some fabric that included a map of Italy, one of the places Max hopes to visit someday.

I also decided that to signify the milestone of Max striking out on his own for real, he should cut the sheet himself, for the first time. So I drew a dotted red line down the middle, as a guide. That turned out to be a pretty powerful moment.

I’ve saved all of these sheets, and Max has asked that eventually I should cut out his favorite bits and make a quilt or wall hanging. I explained that since I used water soluble paints, this can never be washed, and he’s cool with that. The lesson in all of this to me is that the simplest materials can help us celebrate those we love in very profound ways. Clearly, I’ve got only average artistic ability, but I found a way to make these birthdays really stand out and feel special, to help him really feel more palpably a sense of growth and change. I share this with you, hoping that some part of it speaks to or inspires you in your own search for making meaning.